using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;

namespace _1BT01
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }
        

        private void label4_Click(object sender, EventArgs e)
        {

        }

        private void button1_Click(object sender, EventArgs e)
        {
            Point A = new Point(double.Parse(txtXA.Text), double.Parse(txtYA.Text));
            Point B = new Point(double.Parse(txtXB.Text), double.Parse(txtYB.Text));
            Point C = new Point(double.Parse(txtXC.Text), double.Parse(txtYC.Text));
            double chuvi = A.ChieuDai(B) + B.ChieuDai(C) + C.ChieuDai(A) ;
            txtChuVi.Text = chuvi.ToString();
        }
    }
}